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In recent years, mechanochemistry has been growing into a widely accepted alternative for chemical synthesis. In addition to their efficiency and practicality, mechanochemical reactions are also recognized for their sustainability. The association between mechanochemistry and Green Chemistry often originates from the solvent-free nature of most mechanochemical protocols, which can reduce waste production. However, mechanochemistry satisfies more than one of the Principles of Green Chemistry. In this Review we will present a series of examples that will clearly illustrate how mechanochemistry can significantly contribute to the fulfillment of Green Chemistry in a more holistic manner.

Soil organic carbon (SOC) is traditionally measured through dry combustion of soil but is inaccurate in soils recently limed or containing carbonates. Soils of south central Idaho contain carbonates therefore 3 alternative methods are typically used. Walkley-Black titration (WBTIT) has an extensive history but generates a large volume of hazardous waste for each sample analyzed. Low temperature loss on ignition (LOI360°C) may be utilized but requires frequent sample manipulation and is therefore prone to human error. A pressure calcimeter (Pcal) may be used, however the sample container may leak leading to inaccurate results. Therefore, a new method of SOC determination (WBSPEC) utilizing a microplate spectrophotometer was compared to LOI360°C, Pcal, and WBTIT in 75 south central Idaho soils and 10 standard soils. First, it was confirmed that soils of south central Idaho contain carbonates leading to inaccurate SOC determination by dry combustion. During the alternative method comparison, the WBSPEC method reduced waste production over the traditional WBTIT method by 89% while reducing sample handling over LOI360°C. The LOI360°C and WBTIT methods were most similar, however, the WBSPEC method performed adequately; the Pcal method often overestimated SOC compared to each other method. As the low SOC soils of south central Idaho were of particular interest, the methods were compared a second time on low SOC (

Healthcare waste is likely to increase with a rise in the global population and access to medical care. The main reasons to optimise waste management are the statutory duty of care, to reduce environmental impact, for the health and safety of personnel and to reduce financial costs. Working up the waste hierarchy, the priority must be the initial prevention of waste production. This article provides a guide to managing healthcare waste and ways to try and reduce its environmental impact.

Annulation has received steadily growing interest in the interplay with the increasing emphasis towards selective C-H bond functionalization reactions. Metal-free oxidative annulation through functionalization of inert and abundant C-H bonds offers great improvements in terms of atom- and step-economics as well as reduced waste production under mild reaction conditions. Annulation is considered to be a highly efficient strategy for the construction of cyclic molecules because at least two new bonds are formed within a single reaction step. The combination of annulation and direct C-H bond functionalization allows the efficient and straightforward synthesis of carbo- and heterocyclic molecules using simple and non-prefunctionalized precursors. This Concept highlights novel strategies and recent breakthroughs for metal-free annulation through C-H bond functionalization giving access to a variety of important structural motifs.

Cyclisation reactions have always drawn the attention of organic chemists in pursuit of methods for the selective construction of natural-product-like polycyclic compounds. The search for new and efficient ring-forming reactions has witnessed growing interest, resulting in the design of many elegant synthetic strategies and the discovery of useful methodologies. In this context, cycloisomerisation reactions are very attractive, because they allow for the rapid generation of molecular complexity with use of a low loading of a promoter, thus limiting waste production. The search for sustainable and more efficient catalytic systems remains challenging. Relatively nontoxic and inexpensive bismuth(III) salts are of particular interest for catalytic organic synthesis. More specifically, the highly active triflate salt is known to be noncorrosive and easy to handle. This microreview focuses on cyclisation reactions assisted by bismuth(III) triflate catalysis.

The aim of this research was to define the performance of rubber glove products manufactured from concentrated latex using eco-efficiency. Data were collected from two concentrated latex and two rubber glove industries between 2009 and 2011 for the case study to define the eco-efficiency by comparing product values and environmental impact indicators. Eco-efficiency trends of rubber glove products manufactured using concentrated latex production were analyzed using a snapshot graph. The results indicated that the highest and lowest eco-efficiency values of rubber glove products manufactured from concentrated latex were waste production and energy consumption, respectively. Eco-efficiency trends of rubber glove products manufactured from concentrated latex pertaining to material consumption, energy consumption, chemical consumption, and waste production were observed as being half eco-efficient. In addition, the hotspot of high environmental burden of rubber glove products manufactured from concentrated latex was found to be in the process of manufacture. The definition of eco-efficiency values and trends for rubber glove products manufactured from concentrated latex mentions that energy and chemical consumptions cause dominant environmental problems. Therefore, the master approach to eco-efficiency enhancement of rubber glove products manufactured from concentrated latex developed with the four case study industries were as follows: (1) the load factor use of electricity per month, (2) increasing measurements of reduction in energy efficiency in the office concerning concentrated latex process, and (3) the installation of the production line using latex glove processes. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 802–808, 2015

Background To date there have been no comprehensive, comparative assessments of the environmental impact of surgical modalities. Our study seeks to quantify and compare the total greenhouse gas emissions, or 'carbon footprint', attributable to three surgical modalities. Methods A review of 150 staging procedures, employing laparotomy (LAP), conventional laparoscopy (LSC) or robotically-assisted laparoscopy (RA-LSC), was performed. The solid waste generated (kg) and energy consumed (kWh) during each case were quantified and converted into their equivalent mass of carbon dioxide (kg CO2e) release into the environment. The carbon footprint is the sum of the waste production and energy consumption during each surgery (kg CO2e). Results The total carbon footprint of a RA-LSC procedure is 40.3 kg CO2e/patient (p < 0.01). This represents a 38% increase over that of LSC (29.2 kg CO2e/patient; p < 0.01) and a 77% increase over LAP (22.7 kg CO2e/patient; p < 0.01). Conclusions Our results provide clinicians, administrators and policy-makers with knowledge of the environmental impact of their decisions to facilitate adoption of sustainable practices. Copyright © 2015 John Wiley & Sons, Ltd.

Coordination of a chiral substrate to (meso-salen)cobalt(II) nitrate and subsequent oxidation generates a Co(III) complex exhibiting a strong chiroptical readout that is attributed to spontaneous substrate-to-ligand chirality imprinting. The characteristic circular dichroism (CD) response of the (salen)cobalt complex can be used for enantiomeric analysis of a variety of chiral substrates based on a simple CD measurement at low concentration and without additional purification steps. This chirality sensing approach has potential for high-throughput enantiomeric excess (ee) screening applications and minimizes solvent waste production. Chirality 26:379–384, 2014. © 2014 Wiley Periodicals, Inc.

Microwave-assisted three-component reaction has been established for the synthesis of benzodiazepines. This reaction promoted by HOAc was conducted by using readily available and inexpensive starting materials in water under microwave irradiation. The present green synthesis shows fascinating characteristics such as the use of water as the reaction solution, concise one-pot conditions, short reaction periods, easy purification, and reduced waste production without the use of any strong acids or metal promoters.

Energy consumption, water utilisation and waste production are now important environmental issues. However, compilations of data are not readily available, making it difficult for companies to assess how they are performing. This review aims to summarise the data that are available, including some benchmarking values. Also discussed are techniques for reducing water and energy consumption and waste production, tools for monitoring this and assistance that is available to improve efficiency ratios and reduce costs associated with these issues. Using information in this review, an individual company should be able to compare its performance against others producing similar products, nationally or globally in order to set and maintain rational benchmarking values to improve its performance and deal with environmental concerns.

Effects of dietary phytase, amino acid (AA), and inorganic phosphorus (P) in soybean meal (SBM) diets on the growth, feed utilization, and P waste of Australian catfish, Tandanus tandanus, were evaluated. In Experiment 1, SBM replaced 30% of fishmeal (FM) protein in the four test diets, supplemented with phytase (1000-3000 FTU/kg). In Experiment 2, SBM replaced 45% of FM protein in the four test diets, supplemented with phytase, AAs, inorganic P, or their combinations. Inclusion of 3000 FTU/kg significantly improved growth performance and feed utilization of catfish. Ortho-P waste was significantly lower in fish fed with SBM diets. At 30% FM protein replacement, dietary SBM did not reduce the total P waste of catfish while dietary phytase significantly did. At 45% FM protein replacement, phytase alone did not significantly improve the growth and feed utilization of catfish fed with SBM diets while significantly better results were obtained when both phytase and AAs were supplemented. Dietary inclusion of inorganic P significantly decreased P utilization and increased P waste of the fish. Dietary phytase significantly improved P utilization of catfish in both experiments.

Sequential injection analysis (SIA) technique with a miniaturized fibre optic spectrophotometry was exploited to optimize and validate a new method for the assay of verapamil in pharmaceutical formulations. The reduction of acidified permanganate by verapamil was spectrophotometrically detected at 546 nm. The 23 full-factorial design was adopted for screening the effect of conditions controlling the proposed method, and accordingly for the purpose of optimization. The remarkable advantages of the method are high rapidity (sample frequency was 10.6 samples/h), saving in reagents and sample (total consumed volume was 190 µl) and better safety for the environment (total waste production volume was 2140 µl). Additionally, the method was selective in the presence of excipients usually found in tablet and injection formulations. The average of recovery in synthetic samples as well as dosage forms was 98.8–103.0%. The obtained results were realized by the British Pharmacopoeia method and comparable results were obtained. Copyright © 2011 John Wiley & Sons, Ltd.

Avian scavengers are common and active in the social life of southern Ghana, yet few studies consider both the ecological factors for avian presence and the avian-human interactions from human gender and age perspectives, and compare avian behaviour in both human-dominated and natural landscapes. This paper examines interactions between people, hooded vultures and pied crows in Accra and Kumasi, Ghana using both ecological and social research methods. Land use was classified for species presence into meat and waste production, vegetable marketing, non-food production, residential and central business areas, green spaces and rural areas. One hundred and eighty-four people were interviewed, classified according to age and gender. Hooded vultures and pied crows were more common in urban than rural areas, and their presence was positively correlated with human numbers. Birds were most common in meat and waste production areas, but also foraged for street discards in non-food production and residential areas, and were most rare in rural areas. Bird consumption of waste was viewed positively, while eating of other foods, close proximity and unusual behaviours were viewed negatively. Both species, especially the larger vultures, were feared as spiritual agents, this measured by odd behaviours. Women and older people had stronger beliefs, due to cultural conditioning. These human perspectives and reactions influenced avian presence. This study contributes to urban avian ecology, socio-cultural studies and urban planning.

This paper combines a gravity model with country characteristics to examine trade in hazardous waste. A significant pollution haven effect is observed as rising per capita income reduces the amount of hazardous waste countries’ import. However, this effect is outweighed by high-income countries’ relative capital abundance, and by rising GDP creating larger increases in disposal capacity than waste production. Simulating the volume and direction of hazardous waste trade in the absence of distance costs, leads to a 153% increase in waste traded, and a larger increase in shipments from non-OECD countries to OECD members than from the OECD to nonmembers.

More than twenty new alternative methods for bromination of alkenes have been evaluated taking into consideration their resource demands, waste production as well as environmental, health and safety aspects. The cost of bromine and the substances designated to circumvent the application of molecular bromine have also been taken into account. As bromine is only one of several problematic substances being used, its avoidance-by applying bromine supported on solid material or by performing the in situ generation of bromine-does not significantly reduce the technological requirements. On the contrary, the resource demands and amount of waste produced by most new methods are significantly higher compared to the standard methods, especially if the recycling of a carrying agent is not efficient. The method using hydrobromic acid and hydrogen peroxide can be regarded as a competitive alternative to the standard method. The application of certain carrying agents could be interesting, because solvents such as carbon tetrachloride or chloroform used during synthesis could be replaced with less problematic ones during work-up. However, problems associated with these alternatives are not resolved as yet.

Pushed by the increasing demand for materials, energy and products, chemical engineering today faces a crucial challenge: to support a sustainable industrial growth. One possible solution is process intensification (PI), the innovative design strategy aiming to improve manufacturing and processing by decreasing the equipment size/productivity ratio, energy consumption and waste production using innovative technical solutions. Membrane processes meet the requirements of PI because they have potential to replace conventional energy-intensive techniques, to accomplish the selective and efficient transport of specific components, and to improve the performance of reactive processes. Here, we identify the most interesting aspects of membrane engineering in some strategic industrial sectors. The opportunity to integrate conventional membrane units with innovative systems in order to exploit the potential advantages coming from their synergic applications is also emphasized. Copyright © 2007 Society of Chemical Industry

An experiment was conducted with 12 grower pigs to determine the effects of (1) manipulating dietary neutral detergent fibre (NDF) level and (2) dietary inclusion of fibre-degrading enzymes on nutrient digestibility and excreta characteristics in pigs. Four diets were formulated to contain three levels of NDF: 1, 66 g kg−1 NDF (low fibre); 2, 121 g kg−1 NDF (moderate fibre); 3, 222 g kg−1 NDF (high fibre); 4, diet 3 plus 2.0 g kg−1 enzyme. Increasing levels of dietary NDF linearly decreased dry matter and energy digestibilities (r2 = 0.99, P

A convenient synthesis of aryl- and heteroaryl tert-butyl esters from boronic acids (I) or boronic acid pinacol esters (IV) under mild nontoxic conditions with minimal waste production is presented.

Enhancing the efficiency of the synthesis of complex organic products constitutes one of the most exciting challenges to the synthetic chemist. Increasing the catalogue of reactions that are simple additions or that minimize waste production is the necessary first step. Transition metal complexes, which can be tunable both electronically and sterically by varying the metal and/or ligands, are a focal point for such invention. Except for catalytic hydrogenation, such methods have been rare in complex synthesis and virtually unknown for CC bond formation until the advent of cross-coupling reactions. These complexes may orchestrate a variety of CC bond-forming processes, important for creation of the basic skeleton of the organic structure. Their ability to insert into CH bonds primes a number of different types of additions to relatively nonpolar π-electron systems. Besides imparting selectivity, they make feasible reactions that uncatalyzed were previously unknown. The ability of these complexes to preorganize π-electron systems serves as the basis both of simple additions usually accompanied by subsequent hydrogen shifts and of cycloadditions. The ability to generate “reactive” intermediates under mild conditions also provides prospects for new types of CC bond-forming reactions. While the examples reveal a diverse array of successes, the opportunities for new invention are vast and largely untapped.

A survey highlighting the most recent palladium catalytic systems produced and their performances for progress in direct synthesis of indole backbones by heterocarbocyclization of reactive substrates is provided. The discussion is developed in relation with the principles of sustainable chemistry concerning atom and mass economy. In this respect, the general convergent character of the syntheses is of particular interest (one-pot, domino, cascade or tandem reactions), and the substrates accessibility and reactivity, together with the final waste production, are also important. This critical review clearly indicates that the development of ligand chemistry, mainly phosphines and carbenes, in the last few decades gave a significant impetus to powerful functionalization of indoles at virtually all positions of this ubiquitous backbone (118 references).

New regio- and chemoselective [4+2+1] domino cyclization consisting of the formation of two spiro rings and five σ bonds has been developed for the synthesis of spiro-substituted benzo[b]furo[3,4-e][1,4]diazepine derivatives. The reaction is a multicomponent domino green process and can be readily performed by reacting inexpensive starting materials of benzene-1,2-diamines, tetronic acid and 2,2-dihydroxy-2H-indene-1,3-dione in aqueous solution under microwave irradiation. The present synthesis shows attractive characteristics, such as the use of water as reaction media, convenient one-pot operation, short reaction periods of 10–18 min and reduced waste production without the use of any strong acids or metal promoters. This synthesis serves as a nice addition to GAP (Group-Assistant-Purification) chemistry in which purificationviachromatography and recrystallization can be avoided, and the pure products were obtained simply by washing the crude products with 95% EtOH.

The green protocol for the synthesis of title compounds, e.g. (IV), (VI) and (IX), has the advantage of water as reaction medium, simple conditions, easy work-up and reduced waste production.

Enhancing the efficiency of the synthesis of complex organic products constitutes one of the most exciting challenges to the synthetic chemist. Increasing the catalogue of reactions that are simple additions or that minimize waste production is the necessary first step. Transition metal complexes, which can be tunable both electronically and sterically by varying the metal and/or ligands, are a focal point for such invention. Except for catalytic hydrogenation, such methods have been rare in complex synthesis and virtually unknown for CC bond formation until the advent of cross-coupling reactions. These complexes may orchestrate a variety of CC bond-forming processes, important for creation of the basic skeleton of the organic structure. Their ability to insert into CH bonds primes a number of different types of additions to relatively nonpolar π-electron systems. Besides imparting selectivity, they make feasible reactions that uncatalyzed were previously unknown. The ability of these complexes to preorganize π-electron systems serves as the basis both of simple additions usually accompanied by subsequent hydrogen shifts and of cycloadditions. The ability to generate “reactive” intermediates under mild conditions also provides prospects for new types of CC bond-forming reactions. While the examples reveal a diverse array of successes, the opportunities for new invention are vast and largely untapped.

More than twenty new alternative methods for bromination of alkenes have been evaluated taking into consideration their resource demands, waste production as well as environmental, health and safety aspects. The cost of bromine and the substances designated to circumvent the application of molecular bromine have also been taken into account. As bromine is only one of several problematic substances being used, its avoidance-by applying bromine supported on solid material or by performing the in situ generation of bromine-does not significantly reduce the technological requirements. On the contrary, the resource demands and amount of waste produced by most new methods are significantly higher compared to the standard methods, especially if the recycling of a carrying agent is not efficient. The method using hydrobromic acid and hydrogen peroxide can be regarded as a competitive alternative to the standard method. The application of certain carrying agents could be interesting, because solvents such as carbon tetrachloride or chloroform used during synthesis could be replaced with less problematic ones during work-up. However, problems associated with these alternatives are not resolved as yet.

An atom-economic solvent-free synthesis of amides by the Ritter reaction of alcohols and nitriles under microwave irradiation is reported. This green protocol is catalyzed by solid-supported Nafion®NR50 with improved efficiency and reduced waste production.

Formic acid (85%) was added to wilted perennial ryegrass (36% dry matter) at the rate of 0.39%. Changes during ensilage of this material were compared with changes occurring during ensilage of untreated wilted ryegrass and freshly harvested herbage. All silages were well preserved, of low volatile N content and contained only traces of butyric acid. Formic acid restricted fermentation in the wilted grass resulting in silage of high water-soluble carbohydrate content (15.3%) compared with untreated wilted (4.7%) and fresh (1.2%) silages. Results of microbiological studies indicated that yeasts were more active in the formic acid-treated herbages. Surface waste production and fermentation plus oxidation losses were higher in the acid-treated wilted silages (21%) than in the untreated wilted materials (14%).